Marine Geology/Geophysics department is mandated to conduct research into
the topography and geological features of the sea bed and the territorial
waters of Nigerian and the high seas beyond.
The department has five
sections namely:
- Geophysics
- Sedimentology
- Micropaleontology
- Climate Change
- Geochemistry
The department has
five sections namely:
Geophysics
Sedimentology
Micropaleontology
Climate Change
Geochemistry
PROJECTS ONGOING
1. GEOPHYSICAL
STUDY OF THE NIGERIAN CONTINENTAL
SHELF AND DELIMITATION OF THE
NIGERIAN CONTINENTAL
SHELF
The geophysical mapping employing seismic, gravity and magnetics methods constitute major tools for understanding the earth
including the bottom of the ocean and the subsurface. The Nigerian
continental shelf is rich both in fuel and non-fuel minerals. Fish and
fisheries resources are also abundant. These geophysical methods are
used to explore and exploit these resources.
The objective of this project is to unravel the shallow
subsurface geology of the Nigerian Continental shelf using geophysical
techniques (Seismic, Gravity and magnetic).
This project will also gather data and information necessary for the
delimitation of the Nigerian Continental Shelf. This will be in line
with the implementation of the Law of the Sea Article 76 paragraph 9
which states that: "The Coastal States shall
deposit with the secretary-general of the United Nations Charts and
relevant information including geodetic data, permanently describing the
outer limits of its continental shelf. The Secretary General shall give
due publicity thereto".
Other objectives include using side scan sonar and remote
sensing techniques to understand geological/physical processes of the
coastal and marine environment. Knowledge of such processes is relevant
to shelf sediment dynamics, mineral exploration, tectonic hazards and
exploitation as well as development of an Integrated Coastal Zone
Management plan.
HIGHLIGHT OF ACHIEVEMENT
- Dead coral banks on the Western Nigerian
continental shelf mapped
Sediment types and distribution documented
Bathymetric Survey of Lagos lagoon
Bathymetric charting of near shore Victoria
IslandHydrographic and geophysical survey of Benin
and Escravos river`
2. RESEARCH INTO
COASTAL EROSION, OCEAN DYNAMICS
The project is designed to cover the entire Nigerian
coastline stretching over 850 km. Coastal erosion is a major
environmental problem along the entire Nigerian coastline. The aim of
the project is to identify areas along the Nigerian coastline that are
most vulnerable to erosion and measure the actual erosion
rates and the oceanographic parameters responsible for the observed
erosion rates.
The project is expected to:
Identify and measure physical processes of
the ocean such as waves, tides, current, sediment load as well as
meteorological parameters of air temperature, wind speed and direction,
wind gust and barometric pressure.
Establish a data bank for coastal and ocean
dynamics.
To carry out mathematical models of the
Nigerian coastal dynamics with the ultimate objective of predicting
future morphological trends of coast and coastal processes.
To use the data collected and other
environmental data as input into an integrated coastal Zone management
plan.
The project is executed as follows:
- Monthly beach profiling at the 14 established
station and littoral observation including coastal processes data along
the Victoria beach Lagos and at other out stations along the entire
Nigerian coastline.
Weekly down loading of tidal and meteorological
data continued during the year. Compilation of tidal data from the
analogue tide gauge.
Down loading oceanographic data collected by
the Voluntary observing ship Clipper Sao Louis with Shipboard
Environmental Data Acquisition System (SEAS II)
HIGHLIGHTS OF ACHIEVEMENTS
A. BEACH EROSION
Rates of erosion at established stations determined as
follows:
- Lagos Bar Beach: 25 -30 m
per annum
Escravos/Ugborodo: 20 - 25 m
per annum
Forcados 16-20
m per annum
Brass 15
- 20 m per annum
Bonny 10 -
14 m per annum Construction of a T groin and a shore parallel
breakwater along the beach fronting the FCFMT Lagos
B. SEA LEVEL RISE
MONITORING AND EFFECTS ON THE
NIGERIAN COASTAL
ZONE
- Installation of 2 tide gauges (analogue and
acoustic type)
- Data bank on meteorological parameter such as:
air
temperature, water temperature, wind speed, wind direction,
wind gust
and barometric pressure established
- Video mapping of the Nigerian Coastal Zone.
The study
yielded data and information on coastal configuration, coastal
infrastructure, coastal dynamics and socio-economic
activities. The result
of this study indicated that with an
estimated 1-metre sea level rise,
Nigeria could loose over
18,000 km2 of coastal land. The
barrier-lagoon coastline in the
west could loose over 550 km2
of land by the year 2100 with a
1- metre sea level rise while the Strand
Coast in the east could
loose over 400 km2 of land.
C. WORLD
OCEAN CLIMATE EXPERIMENT
(WOCE)/TROPICAL OCEAN AND GLOBAL ATMOSPHERE
PROJECT (TOGA) UTILISING SHIPBOARD AND
ENVIRONMENTAL DATA ACQUISITION SYSTEM (SEAS)
- Collection of oceanographic and
meteorological data
in the Central
Atlantic along route AX-14 (Lagos and
Rio (Brazil) in the South Atlantic
- Collection of depth/temperature profile along
the route AX-14.
- Data complements World Climate Research
Programme
3.
GEOLOGICAL STUDY OF ESTUARIES ON THE EASTERN FLANK OF
THE
NIGER DELTA
The estuaries on the eastern flank of the Niger Delta
(New Calabar, Bonny and Andoni) are presently the sites of many economic
activities related to oil exploration and exploitation. The estuaries
also serve as breeding grounds for some commercially important species
of fish and shrimps. Scientific information on geological processes in
this fragile ecosystem is very important for the sustainable management
of the zone.
HIGHLIGHTS OF ACHIEVEMENT
- Sediment types, distribution, transport and
sedimentation
documented.
- Scientific information available in respect
of physico-chemical
parameters-temperature, pH, Salinity, D.O., alkalinity and
nutrients.
- The use of benthic foraminifera as pollution
indicators in the
Niger Delta estuaries was
established.
4.
THE USE OF REMOTE SENSING AND GIS TO ASSESS SHORELINE
CHANGES BETWEEN THE LIGHTHOUSE AND VICTORIA ISLAND
BEACHES.
The project aims at using satellite imageries and
Geographic Information system coupled with ground truth data to assess
and evaluate the general changes in the morphology and ecology along the
lighthouse and Victoria beach coastline. Analysis Satellite images
covering the project area will assist in the assessment of coastal
dynamics and associated hazards with a regional perspective
to compliment NIOMR's in-situ data.
To achieve these objectives the project:
- Assess general changes in the morphology of
the coastal zone
satellite imageries.
- Compare historical shoreline changes and
trends using GIS.
This project is been implemented through:
-
Establishment of new profile lines and
collection of other ground
truth data like water line, foreshore
gradient, beach configuration
and beach sand grain size.
- Georeferencing and rectification of satellite
images covering the
study sites
- The overlaying of the satellite images on the
digital topographic
map.
HIGHLIGHTS OF ACHIEVEMENTS- Establishment of Geographic Information
System (GIS) and data Centre for analysis, evaluation and management of
coastal and marine data.
Establishment of a GIS database for
the Nigerian Coastal Zone containing georeference
topographic maps and typology attributes.
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Launching a CTD cast at sea
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The Marine Geology/Geophysics Capital project covers the
entire Nigerian Coastal zone and the adjacent Continental margin
(continental shelf, continental slope, continental rise and abyssal
plain). The overall scope of the project involves the collection, analysis
and interpretation of geologic, geophysical, oceanographic data (e.g.
shallow seismic, side scan, wave, tide currents, sediment characteristics
near shore processes etc.) and environmental data from the entire Nigerian
marine and coastal zone. The division carries out this Capital project
under the following sub projects.
Continental shelf
Research into coastal erosion, ocean dynamics
Sea level rise monitoring and effects on the
Nigerian coastal zone.
Shipboard Environmental Data Acquisition System
(SEAS)
Geological study (sediments and microfauna) of
estuaries in the Nigerian Coastal
zone.
Remote Sensing and Geographic Information
System.
Study of main runoff drainage
systems of Victoria and Ikoyi Island in Lagos and
their response to tidal
and sea level changes.
5. STUDY OF MAIN
RUNOFF DRAINAGE SYSTEMS OF VICTORIA AND
IKOYI ISLAND SYSTEMS IN
LAGOS NIGERIA AND THEIR RESPONSE
TO TIDAL AND SEA LEVEL
CHANGES.
Victoria and Ikoyi Islands in Lagos Nigeria constitute
the main barrier island complexes containing both residential,
commercial and tourist facilities in Nigeria. Recent observations have
shown that many of these drainage channels now lack enough drainage
heads to discharge runoffs into the lagoon. This is because these
drainage channels were built without proper information on tidal and sea
level rise. Rising sea level and frequency of storms accompanied by
astronomical high tides are now making these drainage channels
ineffective. This often results in a backup of runoffs in the drainage
channels an eventual flooding of the Island. Such occurrences are most
apparent and disastrous especially during the rainy season and when
storms coincide with high tides resulting in astronomical high tides.
Also the problem of seasonally flooding of the islands is exacerbated by
the dumping of domesticated refuse into the drainage channels this human
activity results in the blockage of the channels resulting in eventual
flooding of the residential and commercial areas of the islands.
The objectives of this survey will be:
- Map the drainage channels on the islands,
- Survey the main drainage channels from their
heads to their discharge points
to estimate their capacity to discharge
water to the lagoons.
- Collect and collate past (from old tide gauge
station and the next Generation
tide gauge) tidal data to determine the
most recent mean sea level.
- Collect meteorological data over time in the
area to determine the
meteorological conditions and predict storm
surges.
- Determine the efficiency of the present
drainage systems and make
recommendation to government.
- Undertake a limited public enlightenment
campaign to stop the dumping of
refuse into the drainage channels.
This project is implemented through the following
activities:
- Selected drainage channels are heightened and levelled from the head of the
channel the toe.
- Tidal data are collated from the tied gauge
station in Lagos to determine
mean sea level.
- During flood, areas affected are heightened
and close contours are used to
delineate the areas.
- Picture of drainage channels is taken.
- Hydraulics of drainage channels is analysed.
- Areas prone to flooding will be demarcated on
maps.
- Bathymetric survey of relevant part of the
lagoon will be done.
HIGHLIGHTS OF ACHIEVEMENTS
- A total of 14 drainage channels have so far been
heightened and levelled.
Tidal data have been collated and mean sea
levels are been determined.
Pictures of levelled drainage channels have
been taken. Questionnaires to be
completed by residents usually affected
by floods have been made and are
to be circulated.
- Preliminary assessment of the drainage channels shows
that most of them lack
drainage heads. Most of the drainage channels are
clogged with domestic
waste in most case. Hydraulic analysis of the data
is continuing. Bathymetric
sounding and other fieldwork will be
accomplished in 1999.
6. RESEARCH INTO
ACID-SULPHATE SOILS OF THE MANGROVE
SWAMP IN
THE NIGER DELTA
Research into soils in the mangrove swamps of the Niger
Delta showed that fish ponds constructed on the Chikoko soil contain
potential acid-sulphate materials within the topmost layer.
The study revealed that mangrove soils are saline and
acidic with pH of between 3.1 to 4.0 on the dry state. A reliable
and effective method of tidal flushing was used to reclaim and manage
the soils. Fish production was increased from 125 kg/ha/yr to 535
kg/ha/yr.
This method can be used by fish farmers to increase fish
yield in tidal fish ponds built on acid-sulphate soil.
7. ECONOMIC
POTENTIALS ON NON-FUEL RESOURCES IN THE
NIGERIAN CONTINENTAL SHELF
This study has identified zones of heavy mineral
concentrations on Nigerian submerged beaches in the Western continental
shelf between Badagry and Benin River estuary. Highest concentration
occurs adjacent to the coastline to a depth of which is parallel to the
IOM isobath and also around the Avon canyon.
Weight of heavy minerals recovered in 5 dried sediment
samples ranged from 0.02 to 0.18 g. Heavy minerals identified include;
zircon, tourmaline, garnet, rutile, apatite, ilmenite and sillimanite.
The economic exploitability of these minerals is yet to
be assessed.
8. WORLD OCEAN
CLIMATE EXPERIMENT/TROPICAL OCEAN AND
GLOBAL ATMOSPHERE
Oceanographic and meteorological data of the Central
Atlantic along route AX-14 (Lagos-Rio). Depth/temperature profiles
along the route are plotted. The data collected is part of a Global
Data Bank of the Atlantic Ocean and is also an important input into the
World Climate Research Project.
The Division has been the focal point of research
collaboration between the Department of meteorological services and
NIOMR on the EP-Nino phenomenon. The co-operative study is focused on
gathering and analysis of all available meteorological and
oceanographic data with the aim achieving a more
accurate prediction of El-Nino phenomenon. This
should have positive impact on agricultural planning, water resources
and fisheries management in Nigeria.
9. INTERNATIONAL CRUISE
First IOCEA (Intergovernmental Oceanographic Commission
for the eastern Atlantic) cruise in the Gulf of Guinea using
NIOMR Research Vessel, M. V. Sarkin Baka 10-25 October, 1989.
The cruise provided data on:
- Width of the Continental shelf in the Gulf of
Guinea.
- Bottom features and Physico-chemical
parameters of shelf waters.
- Sediment characteristics and distribution.
- Meteorology and ocean dynamics in the Gulf of
Guinea.
10. CONSULTANCIES
The Division has carried out several consultancy services
including:
- Oceanographic Survey of the Western Nigerian
Continental Shelf for the
Nigerian Navy.
- Offshore site surveys for oil companies - Benin
River, Niger Delta-Off
Forcados, Escravos, Middleton estuaries
- Seabed survey and environmental impact
assessment
- Hydrographic surveys of estuaries along the
Nigerian Coastline
- Bathymetric charting of the near shore ocean
along the Lagos-Ondo State
coastline
- Site selection for Aquaculture
- Monitoring the performance of beach nourishment
along the Victoria beach
- Integrated Coastal Area Management
11.
OTHER INTERNATIONAL
ACTIVITIES
- LOICZ - regional node for the Land and Ocean
Interaction of the Coastal
Zone (LOICZ) of the International Geosphere -
Biosphere program
(IGBP).
- Regional node for programmes of the
Intergovernmental
Oceanographic
Commission of the Eastern Atlantic (IOCEA) region:
- GLOSS - Global Level of the
Sea Surface
- IODE - International
Ocean Data Exchange
- C-GOOS - Coastal
Module of Global Ocean Observing system |
